Brendan Gleeson and Frances de la Tour have been added to the cast for the fourth Harry Potter film, The Goblet of Fire.

Belfast-born Gleeson, a former secondary school teacher, will play Mad Eye Moody, the latest in a series of increasingly deranged Defence Against the Dark Arts instructors, a former tracker-down of dark wizards and a man apparently with eyes in the back of his head.

De la Tour, who is best known for her role in the 1970s sitcom Rising Damp, will play French schoolmistress Madame Maxime, a flamboyant, larger-than-life character with a closely-guarded secret. She arrives at Hogwarts with her students from the French school of magic, Beauxbatons, to watch one of her pupils take part in an inter-school wizardry competition.

The casting news was revealed by producer David Heyman on the BBC television children's new programm Newsround as the worldwide publicity machine surrounding third film The Prisoner of Azkaban moves into top gear.

Sunday saw latest episode's world premiere in New York, where 14-year-old star Daniel Radcliffe, who plays Potter, was stunned by the excited reaction of a crowd of mostly teenage girls.

The fourth film is being directed by Four Weddings and a Funeral's Mike Newell. Harry Potter and the Prisoner of Azkaban is released in the UK on Monday May 31.